High-availability (HA) cluster is a system of multiple network devices, such as computers, working together to provide network resources for one or more client nodes in a communication network, and operates through redundancy processing to provide uninterrupted server application. Each computer functioning as a network device of an HA cluster may be regarded as a physical host node. When a physical host node is unavailable or cannot handle a client's request for other reasons, the request will be forwarded to another available physical host node in the cluster without any intervention from the client—the cluster system performs the location of available resources and completes the forwarding of the request automatically without user input. In an HA cluster environments (such as Heartbeat- or Corosync-based cluster system), as resources are shared, there is a need to protect the security and consistency of the shared data from a malfunctioning physical host node to prevent data corruptions or a system crash. For example, a cluster manager may fence abnormal physical nodes or physical nodes which have become inactive in order to prevent access to shared resources by those nodes.